In recent years, wireless power supply systems, for example, a system in which a source machine wirelessly supplies electric power to a destination machine, have been proposed.
For example, a primary power-supplying coil is provided in the source machine and a secondary power-supplying coil is provided in the destination machine.
It is desirable to wirelessly supply electric power from the primary power-supplying coil to the secondary power-supplying coil with little energy loss
FIGS. 11A and 11B illustrate the concept of a wireless power supply system.
FIGS. 11A and 11B are disclosed in U.S. Pat. No. 8,035,255.
Moreover, when electric power is wirelessly supplied from the primary power-supplying coil to the secondary power-supplying coil, it is desirable that the way to use the system be easy.